RESUMEN
Pentafluoroaryl analogues have been found to exhibit para specific nucleophilic aromatic substitution (SN Ar). Herein, we describe the use of SN Ar chemistry to create luminous perfluorinated symmetrical terphenyls. Both of SN Ar chemistry and copper(I)-catalysed decarboxylative cross-coupling were applied for the synthesis of the perfluorinated symmetrical terphenyls in high yields from the corresponding derivatives of aryl iodide and potassium salt of fluorobenzoate. A series of perfluorinated symmetrical terphenyls with different para alkoxy chains were synthesized. The synthesized perfluorinated terphenyl adducts were confirmed via elemental analysis, Fourier-transform infrared (FTIR), proton (1 H) carbon-13 (13 C) and fluorine-19 (19 F) nuclear magnetic resonance (NMR) spectra. The absorbance and fluorescence spectra showed solvatochromic activities. The new synthesized fluoroterphenyl hybrids were screened against antioxidant inspection over DPPH (2,2-diphenyl-1-picrylhydrazyl) performance, in assessment of vitamin C and butylated hydroxytoluene (BHT) as standard drugs exposed that fluoroterphenyl hybrid covering decyl hydrocarbons exhibited highest effectiveness through half maximal inhibitory concentration (IC50 ) values of 21.74 µg/ml. Additionally, molecular docking procedures of the synthesized fluoroterphenyl hybrids were employed by using protein data bank (PDB ID: 5IKQ). The docking simulation displayed convenient and recognized findings with the antioxidant examination.
Asunto(s)
Antioxidantes , Cobre , Antioxidantes/química , Simulación del Acoplamiento Molecular , Ácido Ascórbico , Espectroscopía de Resonancia MagnéticaRESUMEN
Cosensitization of the semiconducting electrode in dye-sensitized solar cells (DSCs), with two or more light-harvesting dyes, is a chemical fabrication method that aims to achieve a panchromatic absorption spectrum emulating that of the solar emission spectrum. In this paper, SQ02 and BP-2 cosensitizers have been investigated, as isolated monomers/dimer and adsorbed monomers/dimer on the TiO2 (101) anatase surface, by employing density functional theory (DFT) and time-dependent DFT calculations. Computed results showed that the dominant electron injection pathway is direct injection from each dye into the conduction band of TiO2. The almost complete spectral overlap between the simulated absorption spectrum of BP-2 and fluorescence emissions of SQ02 implies that excitation energy transfer occurs between cosensitizers via the trivial reabsorption mechanism. However, the results showed very limited unidirectional intermolecular charge transfer (CT) from SQ02 dye to BP-2 dye (0.04 |e-|). Therefore, this study also presents a stepwise molecular engineering of BP-2 dye, aiming at optimizing the cosensitization functionality. First, 14 redesigned dye candidates are reported to identify dyes with photophysical properties matching the requirements for efficient DSCs. Second, the four most promising dyes are shortlisted for testing as cosensitizers with the SQ02 dye. The molecular design factors of cosensitization that need validation are chemical compatibility, availability of CT between cosensitizers, and complementarity of the absorption spectra. This screening suggests the judicious choice of the modeled difluorenyl amine donor-based dye (BP-D4) as a very promising cosensitizer. In particular, the SQ02/BP-D4 dimer showed 10 times larger (0.53 |e-|) unidirectional CT than that of SQ02/BP-2 dimer, in addition to the maximum increased electron population of acceptor moieties upon photoexcitation.
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Colorantes , Energía Solar , Teoría Funcional de la Densidad , Electrones , Modelos MolecularesRESUMEN
The fabrication of colorless and see-through dye-sensitized solar cells (DSCs) requires the photosensitizers to have little or no absorption in the visible light region of the solar spectrum. However, a trade-off between transparency and power conversion efficiency (PCE) has to be tackled, since most transparent DSCs are showing low PCE when compared to colorful and opaque DSCs. One strategy to increase PCE is applying two cosensitizers with selective conversion of the UV and NIR radiation, therefore, the non-visible part only is absorbed. In this study, we report synthesis of novel five UV-selective absorbers, based on diimide and Schiff bases incorporating carboxyl and pyridyl anchoring groups. A systematic computational investigation using density functional theory (DFT) and time-dependent DFT approaches was employed to evaluate their prospect of application in transparent DSCs. Experimental UV/Vis absorption spectra showed that all dyes exhibit an absorption band covering the mid/near-UV region of solar spectrum, with a bathochromic shift and a hyperchromic shifts for Py-1 dye. Computational results showed that the studied dyes satisfied the basic photophysical and energetics requirements of operating DSC as well as the stability and thermodynamical spontaneity of adsorption onto surface of TiO2. However, results revealed outperformance of the thienothiophene core-containing Py-1 UV-dye, owing to its advantageous structural attributes, improved conjugation, intense emission, large Stokes shift and maximum charge transferred to the anchor. Chemical compatibility of Py-1 dye was then theoretically investigated as a potential cosensitizer of a reference VG20-C2 NIR-dye. By the judicious selection of pyridyl anchor-based UV-absorber (Py-1) and carboxyl anchor-based NIR-absorber (VG20), the advantage of the optical complementarity and selectivity of different TiO2-adsorption-site (Lewis- and Bronsted-acidic) can be achieved. An improved overall PCE is estimated accordingly.
RESUMEN
New five rings architecture of 1:1 supramolecular hydrogen bonded (H-bonded) complexes were formed between 4-(2-(pyridin-4-yl)diazenyl-3-methylphenyl 4-alkoxybenzoates and 4-n-alkoxyphenyliminobenzoic acids. Mesomorphic and optical behaviors of three systems designed complexes were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). H-bonded interactions were confirmed via FT-IR spectroscopy. Computational calculations were carried out by density functional theory (DFT) estimation for all formed complexes. Experimental evaluations were correlated with the theoretical predictions and results revealed that, all prepared complexes possessing enantiotropic tri-mesophases with induced smectic C (SmC) and nematic temperature ranges. Moreover, DFT predicted for all formed supramolecular complexes possessing a non-linear bent geometry. Moreover, the π-π stacking of the aromatic rings plays an important role in the mesomorphic properties and thermal stabilities of observed phases. The energy changes between frontier molecular orbitals (HOMO and LUMO) and the molecular electrostatic potential (MEP) of the designed complexes were discussed and related to the experimental results.
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Enlace de Hidrógeno , Cristales Líquidos/química , Sustancias Macromoleculares/química , Teoría Funcional de la Densidad , Espectroscopía de Resonancia Magnética , Microscopía de Polarización , Modelos Químicos , Modelos Moleculares , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Palladium catalysed coupling of the 2-iodoBODIPY 3 with a range of anilines and a primary alkylamine succeeds in generating the corresponding 2-aminoBODIPYs. These 2-aminoBODIPY derivatives are non-emissive and quantum chemical calculations and electrochemistry are consistent with charge transfer from the amine substituent. Attenuation of this charge transfer pathway by conversion of the 1,2-phenylenediamine derivative 9 into the corresponding benzimidazolone 10 restores the fluorescence and has been used as the basis for a fluorescence sensor for phosgene.
RESUMEN
A small series of boron dipyrromethene (BODIPY) dyes has been synthesized whereby the boron atom is constrained in a five-membered ring formed from either o-dihydroxypyridine or o-aminophenol. In the latter case, the amino group has been converted into the corresponding amide derivative so as to curtail the possibility for light-induced charge transfer from strap to BODIPY. These compounds are weakly emissive in fluid solution but cleavage of the strap, by treatment with a photoacid generator, restores strong fluorescence. Surprisingly, the same compounds remain weakly fluorescent in a rigid glass at 80 K where light-induced charge transfer is most unlikely. In fluid solution, the fluorescence quantum yield increases with increasing temperature due to a thermally activated step but does not correlate with the thermodynamics for intramolecular charge transfer. It is proposed that the strap causes rupture of the potential energy surface for the excited state, creating traps that provide new routes by which the wave packet can return to the ground state. Access to the trap from the excited state is reversible, leading to the delayed emission. Analysis of the temperature dependent emission intensities allows estimation of the kinetic parameters associated with entering and leaving the trap.
RESUMEN
Helically chiral N,N,O,O-boron chelated dipyrromethenes showed solution-phase circularly polarized luminescence (CPL) in the red region of the visible spectrum (λem (max) from 621 to 663â nm). The parent dipyrromethene is desymmetrised through O chelation of boron by the 3,5-ortho-phenolic substituents, inducing a helical chirality in the fluorophore. The combination of high luminescence dissymmetry factors (|glum | up to 4.7 ×10(-3) ) and fluorescence quantum yields (ΦF up to 0.73) gave exceptionally efficient circularly polarized red emission from these simple small organic fluorophores, enabling future application in CPL-based bioimaging.
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Boro/química , Colorantes Fluorescentes/química , Porfobilinógeno/análogos & derivados , Quelantes , Dicroismo Circular , Luminiscencia , Mediciones Luminiscentes/métodos , Estructura Molecular , Porfobilinógeno/química , Soluciones , EstereoisomerismoRESUMEN
2-Halogeno BODIPYs undergo copper catalysed nucleophilic substitution with alkyl amines and anilines and an amide to give the corresponding 3-aminoBODIPY derivatives. The substrates are readily prepared by the regioselective 2-halogenation of the chemically robust, preformed BODIPYs thus providing an alternative to direct nucleophilic substitution of the corresponding 3-halogenoBODIPYs which requires regioselective 3-halogenation of the more sensitive dipyrromethane intermediate. 2-Halogenation expands the scope of vicarious substitution of BODIPYs to include weaker nitrogen nucleophiles.
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It is of tremendous economic and environmental significance to obtain a powerful adsorbent for the extraction of Gd3+ from wastewater. Adsorbents derived from cellulosic materials functionalized with specific chelators show great promise for the removal of heavy metal ions from wastewater. The selectivity of these sorbents for metal ions is, however, still rather poor. Here, we present a technique for trapping Gd3+ ions from wastewater by synthesizing Gd3+ ion-imprinted polymers based on isatinhydrazone-functionalized cellulose (Gd-ISH-CE). Not only did isatinhydrazone work as a tridentate ligand to directly provide ligand vacancies and build hierarchy pores on Gd-ISH-CE, but it also enabled cross-linking through the epichlorohydrine cross-linker thanks to its very effective NH2 functionalization. The as-prepared Gd-ISH-CE with ISH functionality shows a high adsorption capacity of 275 mg/g and a rapid equilibration time of 30 min for Gd3+ due to its plentiful binding sites and hierarchical pore structure. Furthermore, Gd-ISH-CE shows very selective capture of Gd3+ over competing ions. By integrating the benefits of ion-imprinting and chelator functionalization methodologies in an effortless manner, this study presents a practical approach to the development of superior materials for Gd3+ recovery.
Asunto(s)
Isatina , Contaminantes Químicos del Agua , Celulosa/química , Aguas Residuales , Gadolinio , Ligandos , Iones/química , Adsorción , Contaminantes Químicos del Agua/químicaRESUMEN
Chitosan was used in this study as the bio-based product for the development of microparticles for the specifically targeted removal of cerium ions (Ce3+) by ion-imprinting technology. A thiosalicylic hydrazide-modified chitosan (TSCS) is produced via cyanoacetylation of chitosan, followed by hydrazidine derivatization to finally introduce the thiosalicylate chelating units. Ion-imprinted Ce-TSCS sorbent microparticles were prepared by combining the synthesized TSCS with Ce3+, crosslinking the polymeric Ce3+/TSCS complex with glutaraldehyde, and releasing the chelated Ce3+ using an eluent solution containing a mixture of EDTA and HNO3. Ce-TSCS had a capacity of 164 ± 1 mg/g and better removal selectivity for Ce3+ because it was smart enough to figure out which target ions would fit into the holes made by Ce3+ during the imprinting process. The kinetic data were well suited to a pseudo-second-order model, and the isotherms were well described by the Langmuir model, both of which pointed to chemisorption and adsorption through Ce3+ chelation. XPS and FTIR analyses demonstrate that the predominant adsorption mechanism is the coordination of Ce3+ with the -NH-, -NH2, and -SH chelating units of the thiosalicylic hydrazidine. These findings provide fresh direction for the development of sorbent materials that can effectively and selectively remove Ce3+ from aqueous effluents.
RESUMEN
In this study, gellan gum (Gel) derivatives were allowed to interact via aqueous Diels-Alder chemistry without the need for initiators, producing a crosslinked hydrogel network that exhibited good potential as a drug carrier using tramadol as a drug model. Hydrogel conjugation was achieved by the synthesis of a maleimide and furan-functionalized Gel, and the pre- and post-gelation chemical structure of the resulting hydrogel precursors was fully investigated. Potential uses of the developed hydrogel in the pharmaceutical industry were also evaluated by looking at its gelation duration, temperature, morphologies, swelling, biodegradation, and mechanical characteristics. The Gel-FM hydrogels were safe, showed good antimicrobial activity, and had a low storage modulus, which meant that they could be used in many biochemical fields. The encapsulation and release of tramadol from the hydrogel system in phosphate-buffered saline (PBS) at 37 °C were investigated under acidic and slightly alkaline conditions, replicating the stomach and intestinal tracts, respectively. The in-vitro release profile showed promising results for drug encapsulation, revealing that the drug could safely be well-encapsulated in acidic stomach environments and released more quickly in slightly alkaline intestinal environments. This implies that the hydrogels produced could work well as polymers for specifically delivering medication to the colon.
Asunto(s)
Hidrogeles , Tramadol , Hidrogeles/química , Polisacáridos Bacterianos/química , Sistemas de Liberación de MedicamentosRESUMEN
Developing an effective adsorbent for Pb2+ removal from wastewater has huge economic and environmental implications. Adsorbents made from cellulosic materials that have been modified with certain chelators could be used to get rid of metal cations from aqueous solutions. However, their selectivity for specific metals remains very low. Here, we describe the synthesis of 4-(2-pyridyl)thiosemicarbazide (PTC) hydrazidine-functionalized cellulose (Pb-PTC-CE), a polymer imprinted with Pb2+ ions that may be used to remove Pb2+ ions from wastewater. Owing to its potent -NH2 functionalization, PTC hydrazidine not only served as an efficient chelator to effectively supply coordinating sites and construct hierarchical porous structures on Pb-PTC-CE, but it also made it possible for cross-linking to occur through the glyoxal cross-linker. The abundant chelators, along with the hierarchical porous construction of the developed Pb-PTC-CE with PTC functionality, result in a greater sorption capacity of 336 mg/g and a short sorption period of 40 min for Pb2+. Additionally, Pb-PTC-CE exhibits highly selective Pb2+ uptake compared to competing ions. This study proposes a feasible methodology for the development of high-quality materials for Pb2+ remediation by combining the advantages of active ligand functionality with ion-imprinting techniques in a straightforward way.
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Celulosa , Contaminantes Químicos del Agua , Aguas Residuales , Plomo , Iones , Agua , Cationes , Quelantes , Contaminantes Químicos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
The current work describes the efficient creation and employment of a new S-citalopram selective polymeric sorbent, made from poly(divinylbenzene-maleic anhydride-styrene). The process began by using suspension polymerization technique in the synthesis of poly(styrene-maleic anhydride-divinylbenzene) microparticles. These were then modified with ethylenediamine, developing an amido-succinic acid-based polymer derivative. The S-citalopram, a cationic molecule, was loaded onto these developed anionic polymer particles. Subsequently, the particles were post-crosslinked using glyoxal, which reacts with the amino group residues of ethylenediamine. S-citalopram was extracted from this matrix using an acidic solution, which also left behind stereo-selective cavities in the S-citalopram imprinted polymer, allowing for the selective re-adsorption of S-citalopram. The attributes of the polymer were examined through methods such as 13C NMR, FTIR, thermogravemetric and elemental analyses. SEM was used to observe the shapes and structures of the particles. The imprinted polymers demonstrated a significant ability to adsorb S-citalopram, achieving a capacity of 878 mmol/g at a preferred pH level of 8. It proved efficient in separating enantiomers of (±)-citalopram via column methods, achieving an enantiomeric purity of 97 % for R-citalopram upon introduction and 92 % for S-citalopram upon release.
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Citalopram , Impresión Molecular , Citalopram/química , Citalopram/aislamiento & purificación , Citalopram/síntesis química , Estereoisomerismo , Adsorción , Polímeros/química , Polímeros/síntesis química , Cromatografía Líquida de Alta Presión/métodosRESUMEN
Developing an efficient adsorbent for Ru3+ ions in wastewater is crucial for both environmental protection and resource recovery. This study introduces a novel approach using cellulose-based adsorbents, specifically modified with furan-thiosemicarbazide (FTC), to enhance their selectivity for Ru3+ ions. By cross-linking the Ru3+/FTC-modified cellulose (FTC-CE) complex with a bis(maleimido)ethane (BME) cross-linker, we created a Ru3+ ion-imprinted sorbent (Ru-II-CE) that exhibits a strong affinity and selectivity for Ru3+ ions. The synthesis process was thoroughly characterized using NMR and FTIR spectroscopy, while the surface morphology of the sorbent particles was examined with scanning electron microscopy. The Ru-II-CE sorbent demonstrated exceptional selectivity for Ru3+ among competing metal cations, achieving optimal adsorption at a pH of 5. Its adsorption capacity was notably high at 215 mg/g, fitting well with the Langmuir isotherm model, and it followed pseudo-second-order kinetics. This study highlights the potential of FTC-CE for targeted Ru3+ removal from wastewater, offering a promising solution for heavy metal decontamination.
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Rutenio , Semicarbacidas , Contaminantes Químicos del Agua , Aguas Residuales , Celulosa/química , Iones , Adsorción , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química , CinéticaRESUMEN
Electrospun glass nanofibers (GNFs) were used to strengthen polycarbonate (PC) to create long-persistent photoluminescent and fluorescent smart materials such as afterglow concrete and smart window. Physical integration of lanthanide-activated aluminate (LA) nanoparticles (NPs) yielded transparent GNFs@PC smart sheets. Spectral investigations utilizing photoluminescence and CIE Lab parameters were performed to confirm that the translucent appearance of GNFs@PC changed to green when exposed to UV light. This fluorescence activity was quickly reversible for the GNFs@PC hybrids with low concentrations of LANPs, which indicate fluorescence emission. Higher phosphor concentrations in GNFs@PC led to longer-lasting afterglow photoluminescence and slower reversibility. The GNFs@PC hybrids showed an emission band detected at 518 nm upon excitation at 368 nm. The morphological characteristics of LANPs and GNFs were analyzed by transmission electron microscopy (TEM), which revealed sizes of 11-26 nm and 250-300 nm, respectively. GNFs were prepared using electrospinning technology and then used as a roughening agent into PC sheets. Morphological characteristics of GNFs and GNFs@PC smart sheets were examined using energy-dispersive X-ray spectroscopy (EDXA), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). The GNFs@PC smart sheets were shown to have enhanced scratch resistance in comparison to LANPs-free PC control sample. Increases in LANPs concentration enhanced both hydrophobicity and UV protection.
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Flurbiprofen (FP) is one of the non-steroidal anti-inflammatory drugs (NSAIDs) commonly used to treat arthritic conditions. FP has two enantiomers: S-FP and R-FP. S-FP has potent anti-inflammatory effects, while R-FP has nearly no such effects. Herein, molecularly imprinted microparticles produced from hydrazidine-cellulose (CHD) biopolymer for the preferential uptake of S-FP and chiral resolution of (±)-FP were developed. First, cyanoethylcellulose (CECN) was synthesized, and the -CN units were transformed into hydrazidine groups. The developed CHD was subsequently shaped into microparticles and ionically interacted with the S-FP enantiomer. The particles were then imprinted after being cross-linked with glutaraldehyde, and then the S-FP was removed to provide the S-FP enantio-selective sorbent (S-FPCHD). After characterization, the optimal removal settings for the S- and R-FP enantiomers were determined. The results indicated a capacity of 125 mg/g under the optimum pH range of 5-7. Also, S-FPCHD displayed a noticeable affinity toward S-FP with a 12-fold increase compared to the R-FP enantiomer. The chiral resolution of the (±)-FP was successfully attempted using separation columns, and the outlet sample of the loading solution displayed an enantiomeric excess (ee) of 93 % related to the R-FP, while the eluent solution displayed an ee value of 95 % related to the S-FP.
Asunto(s)
Flurbiprofeno , Flurbiprofeno/química , Antiinflamatorios no Esteroideos , Celulosa , EstereoisomerismoRESUMEN
Molecular cosensitization is favorable for manipulating solar radiation through the judicious choice of cosensitizers having complementary absorption spectra. For greenhouse-integrated dye-sensitized solar cells (DSCs), the manipulation of solar radiation is crucial in order to maximize the flow of photosynthetically active radiation (PAR) for the effectual photosynthetic activity of plants; meanwhile, non-PAR is utilized in agrivoltaics for generating electricity. In this study, we report the synthesis of novel four UV-selective absorbers, based on the diimide scaffold, functionalized with carboxylate and pyridyl anchoring groups, for adequate adsorption onto the TiO2 electrode in DSC. The UV/Vis absorption spectra of the DMF solution-based free dyes were measured experimentally. Basic photophysical and energetics requirements for operating greenhouse-integrated DSCs were examined at the molecular level via (time-dependent) density functional theory-based calculations. The computational results revealed the outperformance of the biphenyldiimide-structured DI-CA1 dye, especially for maximum charge transferred to its anchor, lower thermodynamic barrier for dissociating the photogenerated exciton, largest Stokes' shift, strong electronic coupling with TiO2 nanoparticles, and higher degree of charge separation at the DI-CA1/TiO2 interface. PDOS showed deeper existence for the LUMO level in the CB of TiO2, which expedites the electron injection process. The chemical and optical compatibility of DI-CA1 were then investigated as a potential cosensitizer of a reference BTD-DTP1, a green light-absorbing dye. Considerable overlap between the fluorescence spectrum of DI-CA1 and absorption spectrum of the reference BTD-DTP1 advocated the opportunity of excitation energy transfer via the radiative trivial reabsorption mechanism, which confirms the cosensitization functionality. Energy decomposition analysis and reduced density gradient maps estimated the chemical compatibility owing to weak dispersion interactions as the dominant stabilizing attractive force. This noncovalent functionalization retains the chemical compatibility without distorting the π-π conjugation and the associated physicochemical properties of the individual dye molecules. Along with the expanded consumption of non-photosynthetically active solar radiation, an improved power conversion efficiency of greenhouse-integrated DSC is accordingly expected.
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To identify new candidate anticancer compounds, we here report the synthesis of benzimidazole derivatives: diethyl 2,2'-(2-oxo-1H-benzo[d]imidazole-1,3(2H)-diyl) diacetate and its arylideneacetohydrazide derivatives, using ultrasonic irradiation and conventional heating. The compounds were confirmed by Nuclear magnetic resonance (NMR) (JEOL, Tokyo, Japan) and Fourier transform infrared spectroscopy (FTIR) spectroscopy (Thermoscientific, Waltham, MA, USA). The molecular structure and electronic properties of the studied compounds were predicted for the acetohydrazide hydrazones. These compounds exist as a mixture of configurational and conformational isomerism as well as amido-amidic acid tautomerism. The NMR spectral data proved the predominance of syn-E amido isomers. In addition, density functional theory (DFT) predicted stability in the gas phase and showed that syn-E amido isomers are the most stable in the presence of an electron donating group, while the anti-isomer is the most stable in the presence of electron-attracting substituents. The anticancer activity of these synthetic compounds 6a, 6b and 6c towards both colon cancer (HCT-116) and cervical cancer (HeLa) cells was examined by MTT assay and DAPI staining. The MTT assay revealed a strong antiproliferative effect against the cancer cells at low concentrations, and interestingly, no significant inhibitory action against the non-cancerous cell line, HEK-293. The IC50 values for HCT-116 were 29.5 + 4.53 µM, 57.9 + 7.01 µM and 40.6 + 5.42 µM for 6a, 6b, and 6c, respectively. The IC50 values for HeLa cells were 57.1 + 6.7 µM, 65.6 + 6.63 µM and 33.8 + 3.54 µM for 6a, 6b, and 6c, respectively. DAPI staining revealed that these synthesized benzimidazole derivatives caused apoptotic cell death in both the colon and cervical cancer cells. Thus, these synthetic compounds demonstrate encouraging anticancer activity as well as being safe for normal human cells, making them attractive candidates as anticancer agents.
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The outstanding biodegradability, biocompatibility, affordability, and renewability of polylactic acid have made it a prominent biomaterial. Herein, an innovative, easy, and eco-friendly technique is used to prepare sodium polylactate (SP)-based nanofibers. Solution blowing spinning (SBS) was used to create fibrous mats of SP and polyvinyl alcohol (PVA). SBS's SP nanfibers were crosslinked using an aqueous solution of calcium chloride to produce moisture-resistant calcium polylactate nanofibrous spun mats. Both of UV-visible absorption spectra and transmission electron microscopy were utilized to study the produced zinc oxide (ZnO) nanoparticles (NPs) to indicate a diameter of around 15-23 nm with a high intensity absorption intensity at 370 nm. New polylactate copolymer was synthesized and characterized by infrared and NMR spectroscopic techniques. In order to prepare SP/PVA/ZnO nanocomposite nanofibers, various ZnO ratios were used. The morphologies of the composite nanofibers were investigated by infrared spectroscopy (FTIR), energy-dispersive X-ray analyzer, and scanning electron microscopy. The cytotoxicity tests of the prepared mat were studied by conducting experiments with L-929 cells at various time intervals. The prepared composite SP/PVA/ZnO nanofibers were subjected to cytotoxicity tests to determine their cytocompatibility. Results showed that those with ZnO concentrations between 0.5% and 2% were found to be less harmful than those with higher concentrations. A variety of bacterial species, including Bacillus pumilus and Staphylococcus aureus, as well as Klebseilla pneumoniae and Escherichia coli, were used to test the antibacterial properties of SP/PVA/ZnO spun mats. The ZnO NPs integrated in the SP/PVA fibrous mats were responsible for their antibacterial properties. After finding the appropriate concentration of ZnO that is least harmful while yet giving a satisfactory antibacterial activity, this biomaterial might be perfect for wound dressing applications. HIGHLIGHTS: New eco-friendly biodegradable sodium polylactate (SP) copolymer was synthesized. Zinc oxide nanoparticles (ZnO NPs) with a diameter of 15-23 nm were prepared. High antibacterial SP/PVA/ZnO fibers were prepared by solution blowing spinning. SP/PVA/ZnO nanofibers (180-220 nm) with various ratios of ZnO were presented. Cytotoxicity results showed that the cell viability decreases with increasing ZnO.
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Nanofibras , Óxido de Zinc , Antibacterianos/farmacología , Antibacterianos/química , Vendajes/microbiología , Materiales Biocompatibles , Escherichia coli , Nanofibras/química , Polímeros , Alcohol Polivinílico/farmacología , Alcohol Polivinílico/química , Sodio , Óxido de Zinc/farmacología , Óxido de Zinc/químicaRESUMEN
Exposure to nerve agents, which are usually colorless and odorless gases, may cause organ failure, paralysis, or even quick death. Diethyl chlorophosphate (DCP) has been recognized as one of the most well-known chemical warfare nerve agent mimics. In the current study, we introduce a simple strategy for the development of a portable and reversible nanocomposite-based microporous strip for naked-eye detection of DCP within a few seconds. A dicyanomethylenedihydrofuran hydrazone (DCDHF-H) chromophore was synthesized by an easy azo-coupling reaction and encapsulated in situ during the preparation of cellulose acetate/cellulose nanowhisker/hydrazone (CA-CNW-H) nanocomposites. These CA-CNW-H nanocomposites displayed a bathochromic shift in the absorption intensity of about 142 nm from 438 to 580 nm with the increase of the DCP concentration. The present CA-CNW-H sensor strip displayed a detection limit for DCP ranging from 25 to 200 ppm. The color change of CA-CNW-H from yellow to purple due to exposure to DCP was detected by CIE Lab analysis. The morphology, fibrous crystallinity, thermal stability, and mechanical properties of the prepared CA-CNW-H sensor strips were investigated.